116 A. WINCHELL — A LAST WORD WITH THE HURONIAN. 



9. Greenstone L 700 ft. 



8. Whitish or whitish gray quartzite passing into quartzose conglomerate 



with blood-red jasper pebbles 1,000 



7. Dark-blue and blackish fine-grained slates with dark-gray quartzite- 500 



6. Slate conglomerate 800 



5. Limestone 250 



4. Slate conglomerate 1,000 



3. Greenish, silicious slates, unstratified, with pale greenish quartzite 1,200 



2. Greenstone 400 



1. Green, altered slates of a chloritic character 1,000 



Mr. Murray recognizes the two slate conglomerates as separated by the 

 limestome, but his language would lead us to suppose them not separated 

 by any considerable amount of other strata ; and he may have overlooked 

 or underestimated such intervening strata under the impression, which he 

 brought from Thessalon valley, that the two slate conglomerates were one 

 formation. He says : 



" Both above and below the limestone the rock is a slate conglomerate, the base of 

 which is usually of a greenish color, frequently having the aspect of an igneous rock ; 

 but it contains numerous rounded pebbles of various kinds, the chief part of which 

 are syenite, quartz, gneiss and jasper. In some cases the conglomerate is very coarse, 

 the pebbles or bowlders, as they may be called, forming the greater part of the mass. 

 In other cases the rock is a fine compact slate, inclosing rounded masses of various 

 sizes and characters, which are scattered through the slate at wide distances from one 

 another." 



" The rocks beneath the lower slate conglomerate are greenish silicious slate and 

 pale-green quartzite. ^ * ^ These are underlaid by greenstone, and below the 

 greenstone is a highly altered green chloritic' slate, which is exposed in nearly ver- 

 tical strata, forming high precipices at the extreme head of the lake.^ 



The limestone between the two conglomerates is set down, meantime, as 

 having an "average inclination of about 25°" (p. 21). 



Mr. Murray speaks of tracing the two conglomerates on their strike south- 

 eastward for a distance of about six miles, and says it is probable that the 

 intervening limestone "holds the same course until it strikes the Thessalon 

 and Ottertail lakes, on the Thessalon river, where it is already known to be 

 exposed." But he nowhere gives a description of either slate conglomerate 

 by itself. 



The Succession on Echo Lake. — Now, let us consider carefully the strati- 

 graphical succession seen along the shores of Echo lake. The upper slate 

 conglomerate lies beneath the low ground which extends for about three 

 miles to the foot of the lake. It is here succeeded (underlain) by a quartzite 

 of a different character from the quartzites above the conglomerate, being, 

 in its lower part, greenish or blackish and slaty. It passes thus from a 



* Geology of Canada, 1863, pp. 22, 23. 



